Forage and Pasture
Forage Management Guides
Self-Study Guide 3: Bermudagrass
Bermudagrass is grown on approximately 2 million acres in Arkansas. Because
of its ruggedness, good quality and dependable yields, it provides the backbone
of the warm-season perennial grass program. It breaks dormancy in spring when
temperatures rise above 60° F and reaches peak production at 85° to 95° F,
giving a productive period from May to September. When teamed with tall fescue
and other grasses that grow best during cool weather, bermudagrass helps provide
year-round pastures for beef, dairy, and sheep producers, as well as pleasure
horse owners. Ideally, bermudagrass or other warm-season grasses should comprise
30 to 50 percent of a farmer’s total forage acreage in north Arkansas and 50 to
65 percent of the total in south Arkansas.
The two main types of bermudagrass are common and hybrids. Common
bermudagrasses are persistent perennials, short, fine-leaved, and fine-stemmed.
Common bermudagrasses produce viable seed in Arkansas, but most seed
commercially used in our state is produced in the western United States. Hybrids
are perennial, tall, coarse-stemmed and large-leaved. Hybrids respond better to
nitrogen fertilizer and usually produce higher forage yields than do varieties
of common bermudagrass. However, most hybrids do not produce viable seed and
must be propagated by sprigging. Giant bermudagrasses are hybrid types that
produce viable seed, but behave as annuals in Arkansas as a result of very poor
winter hardiness.
Bermudagrass spreads by above-ground runners called stolons and underground
runners called rhizomes. Stolons and rhizomes can form leaves and roots at each
node. Stolons and rhizomes can form new roots and leaves at every joint,
creating new plants that can become detached and exist independently of the
parent plant. This trait makes it possible to establish new bermudagrass fields
using transplanted rhizomes (sprigs) from old fields. This is a highly desirable
trait in pastures where spread is wanted, but undesirable if bermudagrass is
growing as a weed in row crops.
Varieties of bermudagrass may be grown in any county in Arkansas. Coastal,
Alicia, Brazos, and Tifton 85 are strains of hybrid bermudagrass that are not
well adapted north of Little Rock because they do not have good winter
hardiness. Tifton 44 and Midland are two hybrid types and Guymon and Greenfield
are two varieties of the common types that are winter-hardy enough to grow as
far north as the Missouri state line, but even these can be damaged in
especially severe winters. The youngest part of stolons normally die back from
the tip each winter or during periods of severe drought. Large, thick rhizomes
are more resistant to winterkill than smaller, thin ones. Stands that have been
stressed in the fall by overgrazing, low soil fertility, or drought may have low
root energy reserves which can lead to severe winter die-back, especially on
varieties or hybrids that are least tolerant of cold winters. Newly planted
fields are susceptible to winterkill in north Arkansas during the winter of
their establishment year unless proper levels of potash are applied and the crop
is planted by the recommended planting date.
Bermudagrass is more drought tolerant than other warm-season perennial
grasses like dallisgrass and bahiagrass. It is adapted to any moderately
well-drained soil, but does not do well on heavy soil (unless irrigated) because
of poor root penetration. It will tolerate soil pH values as low as 5.5, will
tolerate some flooding, but makes little growth in water-logged soils. It will
not survive well in areas immediately above terraces or in low spots in fields
where water stands.
Common Bermudagrass
The term “common” bermudagrass has two meanings. One refers to the general
type of bermudagrass that is fine-stemmed, short, persistent, produces viable
seed and volunteers easily in Arkansas fields, therefore having potential as a
weed pest. Common bermudagrass is grown in preference to hybrids on rough sites
too rocky or steep for haying, on shallow soils, poorly drained soils, or soils
with high water tables. Common bermudagrass is also preferred on fields where
minimal fertilizer will be applied, when the primary use will be pasture rather
than hay, and when sprigging equipment is not available. It is an excellent
pasture plant that can yield roughly 75 percent as much forage as hybrids under
good management. Establishing common bermudagrass from seed is usually less
expensive per acre than sprigging hybrids. Common bermudagrass is not as
productive as hybrid bermudagrass under heavy nitrogen applications, but it out
competes hybrid types for other nutrients when nitrogen fertility is low. For
this reason, hybrid bermudagrass fields may “turn to” common bermudagrass if
both are initially present and nitrogen applications are low.
The second usage of “common” is to describe an unnamed variety of the
seed-producing type of bermudagrass. Seed labeled as common may be a
wild-growing bermudagrass, a mixture of several varieties of bermudagrass, or
seed of a single variety that the seller does not want to guarantee as pure.
Seed of unnamed varieties usually costs less than named varieties.
There are over 150 different strains of common bermudagrass with varying
potential productivities. In general, common types tend to be susceptible to
leaf diseases, susceptible to winter damage in their first year, and have low
productivity in late fall. Yields depend on location, management, and fertility.
Common bermudagrass yields have ranged from 3.4 to 6.6 tons per acre in northern
Arkansas variety tests and 4.7 to 7.0 tons per acre in southern Arkansas. Some
available named varieties are described below.
Greenfield – A fast-growing, winter-hardy bermudagrass with dark green
leaves, purple stolons, and short crooked rhizomes. It is well adapted to low
fertility sites, has good productivity on fine soils, and produces a dense sod.
It is unique among common types for its poor seed production and must be
established by sprigging.
Guymon – A winter-hardy, drought-tolerant bermudagrass released mainly
for turf and conservation, but also with good forage production.
Pasto-Rica – A blend of common and a cold-sensitive giant type that is
adapted for southern Arkansas. It is susceptible to diseases but has excellent
first year productivity and can be grazed the first year. The giant type will be
killed the first winter, leaving only common.
Tierra-Verde – Another blend of common and giant bermudagrass that is
similar to Pasto-Rica.
Hybrid Bermudagrass
Hybrid bermudagrasses are preferred over common types on deep, well-drained,
naturally fertile soils, when high amounts of fertilizer can be applied yearly,
and when the field will be used primarily for hay rather than pasture. Depending
on location, management, and fertility, hybrid bermudagrasses have yielded 3.0
to 8.7 tons per acre in northern Arkansas variety tests and 4.3 to 8.8 tons per
acre in southern Arkansas. Some recommended varieties are described below.
Coastal – A cross between common (Tift) and a South African selection,
it is well-adapted to deep, sandy soils, has good forage quality, an open sod,
good disease resistance, and low tolerance of poorly drained sites. It begins
growing later than common bermudagrass in spring and is best adapted to southern
Arkansas.
Midland – A cold-tolerant cross between common and Coastal that is
more productive than common in hot dry weather and in the fall. It is more
compatible with legumes than common, and less disease resistant than Coastal. It
produces an open sod with low rootstock production per acre, and can be grown
throughout Arkansas.
Alicia – A South African hybrid with an aggressive growth rate and
relatively shallow roots that tolerate poor drainage better than most hybrids.
It has vigorous stems that can be used to establish new stands using stem
cuttings with good success. It is not cold-tolerant enough for northern Arkansas
and is less digestible than Coastal.
Hardie – A somewhat winter-hardy, fast-spreading hybrid with larger
stems and leaves, better digestibility, and faster spring and fall growth than
Midland. It is susceptible to Helminthosporium disease and can be grown
throughout Arkansas.
Stone County Hardie – A winter-hardy, fast-spreading bermudagrass that
forms a dense sod that looks and yields similarly to common bermudagrass in many
fields. It is better for pasture than hay.
Tifton 44 – A high-yielding cross between Coastal and a German
selection that is usually winter-hardy throughout Arkansas, and has better
forage quality, finer stems, and a denser sod than Coastal.
Brazos – Has better animal gains, a more open sod, better tolerance of
heavy soils, slightly more cold tolerance, and earlier spring growth than
Coastal. Rhizomes are large and dense.
Grazer – Adapted to southern Arkansas, this hybrid establishes easily
from sprigs or cuttings, is better for pasture than hay, produces a dense sod
and good late summer animal gains, and is more digestible than Coastal
Oklan – Adapted to southern Arkansas only with less cold tolerance
than Midland. It is resistant to Helminthosporium disease, and can be propagated
by stem cuttings.
Tifton 85 – A robust, thick-stemmed, tall, fast-growing bermudagrass
with broad, dark green leaves and good drought tolerance. It has fewer rhizomes,
higher yield, and less cold tolerance than Coastal, and higher forage quality
than Tifton 44.
Bermudagrass Establishment
There are three ways to start new bermudagrass fields: 1) by seed, 2) by
sprigging, and 3) by using cuttings. Common bermudagrass is most often seeded,
but may be sprigged. Hybrid bermudagrasses do not produce viable seed and so are
usually sprigged and occasionally propagated using stem cuttings.
Starting Bermudagrass from Seed
Seedbeds for establishing bermudagrass should be fertile, free of weeds,
firm, and moist, and soil pH should be above 5.5. Lime is best applied and
incorporated six months prior to planting to allow time for the soil pH to
adjust to the desired level. Fertilizer should be applied according to soil test
recommendations at planting time. Because bermudagrass seedlings are weak
competitors, weeds should be controlled with recommended tillage and herbicide
applications. Because bermudagrass seed are very small (2,071,000 hulled seed
per pound) and easily planted too deep, the field should be disked and rolled
firmly prior to planting. Seed should be placed no deeper than 1/4 inch for best
germination and emergence, and the field should then be rerolled. Hulled seed is
more expensive, but it germinates much better than unhulled seed. In north
Arkansas, 2 to 6 lbs per acre of good hulled seed should be planted between
April 15 and June 15. In south Arkansas, the recommended planting window is two
weeks earlier, from April 1 to June 1.
Applying 45 to 60 lbs of nitrogen to new stands when runners begin to form
encourages spreading. Nitrogen application can be repeated every five to six
weeks until mid-August. Weeds should be controlled until plants are
well-established. When plants are more than 4 inches tall they may be grazed,
and should be rotationally grazed to a 2-inch height as regrowth allows, perhaps
as often as every three weeks. Grazing should be stopped 30 days before frost to
allow plants to accumulate nutrient reserves for winter survival.
Sprigging Bermudagrass
A sprig consists of a short section of runner (rhizome) dug from an
established field. Each sprig contains roots and is capable of producing a new
plant when it is transplanted. A good-sized sprig is at least 6 inches long and
has three or more joints. Dormant sprigs (no green leaves) are more desirable
than non-dormant sprigs (with green leaves), and smaller dormant sprigs are as
good as larger non-dormant ones. The field for sprigging should be prepared the
same way as described for seeding. Sprig mortality may approach 50 percent after
two days in a hot, dry soil, so sprigging is best done the day after a rain.
Sprigs should be transplanted on the same day they are dug if possible, so they
do not die from drying out. If this is not possible, they can be stored in a
cool, moist place for no more than 3 1/2 days. Bermudagrass may be sprigged at
any time of year, but February 15 to June 1 is the time with most favorable
conditions of field accessibility, soil moisture, and temperature. Later
sprigging may result in stand failure due to freezing of poorly developed root
systems the first winter.
Sprigging machines can plant 16 or more bushels of sprigs (one bushel
contains about 1,000 sprigs) per acre. Rates as low as 10 bushels per acre may
be sufficient if sprigs are evenly distributed and covered, but plants may not
grow to complete field coverage in one year. Rates higher than 16 bushels per
acre can be used for faster coverage when cost is not prohibitive. Sprigs should
be planted less than 2 inches deep. Dormant sprigs can be completely covered
with one inch of soil, but non-dormant sprigs should have one-inch sections of
leaves left exposed. Small acreages may be sprigged by hand, placing one sprig
every 2 feet in 36-inch rows. Sprigs may also be broadcast at 25 to 40 bushels
per acre with a manure spreader, covered with a disk, and rolled. Soil should be
well-firmed after planting to improve contact with sprigs and encourage rapid
root development.
If sprigging results in one healthy sprig every 6 square feet and moisture is
adequate, a full stand of grass can be achieved in one year. Some bermudagrass
varieties can cover 20 feet in one year. Under poorer conditions, with one sprig
every 25 square feet, complete stands can be achieved in two years. Application
of 45 to 60 lb per acre of nitrogen fertilizer when plants begin to run and
every 5 to 6 weeks thereafter will encourage faster spreading. Post-emergence
herbicides can be used as needed to control broadleaf weeds.
It is best not to graze newly sprigged fields until coverage is complete, but
cautious grazing or haying during the sprigging year is possible if weeds are a
problem and the waiting period following previous herbicide application is
observed.
It may be profitable to establish a sprig nursery on the farm as a source of
hybrid sprigs. A sprig nursery may even be profitable for common bermudagrasses,
because winter survival is likely to be better the first year with a stand
established from local sprigs rather than seed from a non-Arkansas source.
Well-established nurseries can yield up to 275 bushels of sprigs per acre
harvested two or more times per year. Nurseries should be established in fields
that are free of common bermudagrass and weeds like nutsedge and johnsongrass
that can propagate from roots and rhizomes. Sandy soil makes digging sprigs
easier. Removal of the last year’s growth by burning in spring may also make
digging easier. The best time to burn is one week before the last spring frost
and before the sod breaks dormancy or begins to green up in the spring.
Commercial digging machines are available, or the nursery or old field can be
cross-disked to cut the bermudagrass runners into small sprigs, cultivated with
a spring-tooth harrow to pull up the sprigs, and raked into windrows for
immediate loading.
Establishing Bermudagrass from Stem Cuttings
Cuttings are not often used to establish bermudagrass, and are generally only
used to establish hybrids like Alicia or Oklan that have large, thick runners
above ground and few rhizomes. Cuttings are taken solely from aboveground growth
of established bermudagrass stands, and therefore contain no roots. New root and
leaf growth must be initiated from the nodes on the stem cuttings, which is a
slower and less reliable process than growth from rhizome sprigs. Therefore,
higher planting rates are needed for cuttings than for sprigs. Cuttings are
planted by cutting bermudagrass as if for hay, and then immediately broadcasting
the green hay at a rate of 20 to 40 bushels per acre onto soil prepared as if
for sprigging. The hay should be firmed into the soil using a weighted disk with
disks set straight, and then rolled or cultipacked. After-planting management is
the same as for sprigging.
Bermudagrass Stand Management
Beef and dairy cattle producers are the primary users of bermudagrass in
Arkansas, but the forage is also used for horses, sheep, and goats. Most
bermudagrass is utilized as pasture or hay. As a hay crop, bermudagrass has
several advantages over other forage species. One advantage is that large round
bales of bermudagrass shed water and resist spoilage better than bales of tall
fescue because its relatively fine leaf and stem form a tighter bale. Another
advantage is that bermudagrass hay is harvested during a time of year when
weather conditions are better for field curing, again resulting in less hay
spoilage. Hybrid bermudagrasses are generally ready to be cut for hay when 15
to18 inches tall, and can be cut every 4 to 6 weeks during the active growing
season. For extremely high quality forage, hay can be cut when forage is as
little as 6 inches tall.
As pasture forage, bermudagrass is hard to beat because of its tolerance of
frequent close grazing. It is usually grown in pure stands. On
continuously-stocked pastures, stocking rates should be adjusted to keep the
bermudagrass between 3 and 5 inches tall. Bermudagrass can be rotationally
grazed by moving cattle onto paddocks when 6 to 8 inches of growth has
accumulated, and grazing it down to 2 inches within 7 to 10 days. When cattle
are moved to the next paddock, the exited paddock should be fertilized with
nitrogen to encourage grass growth for the next grazing period and increase
protein content of the forage. Exited paddocks can be clipped if necessary to
remove mature ungrazed forage and reduce selective grazing during the next
occupation period. When more forage is produced than the cattle can utilize as
pasture, the excess can be baled as hay.
Bermudagrass goes dormant during the winter months, but pastures can still be
utilized with careful planning. Annual grasses, legumes, or small grains can be
seeded into dormant bermudagrass sods in autumn to provide cool-season grazing.
This practice will be discussed in Lesson 8. Another method for extending use of
bermudagrass pastures into the winter is to grow bermudagrass in a mixture with
tall fescue. In this case, proper timing of fertilizer application is vital to
ensure persistence of both species. Fescue tends to be more aggressive in this
mixture than bermudagrass, especially when fertilizer is applied during the cool
months of spring when both species are actively growing. Fertilizing with
nitrogen during the warm summer months favors the bermudagrass.
The type of bermudagrass grown (common or hybrid), nitrogen fertilizer
applied, rainfall, and harvest date are the four main factors determining both
tonnage and quality of bermudagrass forage production. Specific variety
differences are much less important. Critical issues regarding N fertilizer are
the amount and timing of application. Bermudagrass should receive no less than
60 pounds of N per acre per year, and can efficiently utilize up to 400 pounds.
In general, bermudagrass requires about 50 pounds of N for each ton of
hay-equivalent forage produced, with yields generally increasing in direct
proportion to the amount of N applied. Greater efficiency of N use occurs when
split applications of N are made. An initial application of 40 to 50 lb N per
acre should be made around April 1, and additional applications of 60 to 100 lb
N per acre (depending on desired yield) should be made after every hay cutting
or after every 4 to 6 weeks of grazing.
Bermudagrass benefits from application of phosphorus and potassium when soil
test results indicate. These nutrients should be applied according to the soil
test recommendations around April 1 or first green-up. To reach highest yield
potential, an additional 80 to 100 lbs K per acre should be applied with the N
after every hay cutting or after every 4 to 6 week grazing period. On weak
stands, a K application just prior to the last grazing or hay cutting helps
insure that plants are healthy going into the winter.
Bermudagrass requires about four inches of water for every ton of dry matter
produced. During late July and August, the crop may require one quarter inch of
water per day. If rainfall is not adequate, the grass tends to go dormant.
Weed control may improve productivity of bermudagrass stands. Proper grazing,
fertilizing, and clipping practices help control weeds and reduce the need for
herbicides. Dicamba, 2,4-D, picloram and metsulfuron are broadleaf weed
post-emergence herbicides currently labeled for use on bermudagrass. Glyphosate
and paraquat are non-selective post-emergence herbicides that may be used to
control winter annual weeds when bermudagrass is dormant. When any herbicides
are used, it is essential that label directions be strictly followed regarding
application rates and withdrawal times for grazing or hay.
Bermudagrass Forage Quality and Animal Performance
Protein concentration and TDN (total digestible nutrients) are the two major
quality factors to consider with bermudagrass. Fertilization and harvest dates
have a greater effect on forage quality than any other management factor.
Bermudagrass generally contains from 4 to 18 percent crude protein, with an
average around 10 percent. Nitrogen fertilization increases the protein
percentage in the forage, with high N rates producing forage with as much as 25
percent crude protein. Reported bermudagrass hay TDN values in Arkansas range
from 40 to 79 percent, with an average of 59 percent. Both protein and TDN are
highest in the very youngest, most tender leaves, and decrease rapidly as plants
elongate with maturity and contain a higher proportion of stem. Haying or
grazing intervals longer than 4 to 6 weeks may produce higher tonnages of
forage, but lower quality and palatability will result in lower forage intakes
and lower animal performance per pound of forage eaten.
For more information about Bermudagrass, contact your county Extension office
or refer to one of our
publications.
Back
to Forage Management Guides
|
